Baja driveline

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How much HP can you put through the Baja driveline, stock, HPI heavy duty upgraded, aftermarket upgraded...?
stock drive shafts nothing it will brake just pushing it lol,heavy duty drive shafts hold up fine to most things of you can get turtle modded drive shafts the only outher suspect thing is the diff but you can get a turtle diff case cover which help reduce twist
How about the gears?

I noticed that HPI has a full set of HD gears, Are they good enough for 4 to 5 hp. range.
pretty well with the HD Drive shafts. the stockers brake, no need for the HD Gear case gears. but the DIFF Gears need to be upgraded BADLY. ofcourse HPI though it best to offer HD Gears for Gears that in stock form, don't have any problems. lol

get a Turtle Racing Diff Saver Case on the diff ASAP, stock motor or otherwise. its a must imo.

other than that. the tranny is pretty tough as is the drive line for the most part.

I started my cleaning of the Baja and found a few items and by the time it ended its in pieces - Again.:) :clown:

So what do you think I will find in the diff case when I remove it?
Timmahh is this the area that breaks on the case? (see vid)
In looking close I think the bearing is even gone on that side.:(
Is it normal for the shaft to move that much? and there is a gap where the shaft enters.

Anyone taken there front tires off to find slop in it? I found slop and a locked bearing, after dismantling the front end removing the bearings, cleaning and re greasing, and reinstalling the slop is gone??? Whats up is there a right or wrong side to install the bearing? The C clip wasn't bent either.

Look here:

I know I should of just gone over to the Baja forum but I'm lazy and like a one shop stop!:clown: :)
ok, the slop in the front was lateral it appeared. ie, side to side only. it didnt appear to go up n down. there is a bit of side to side play, about the same you had. so as long as the bearings are in good shape, and the hub isnt warped out where the bearings go, then i say its normal. maybe a shim or two can releave the extra side to side play you have.

Spur Gear shaft. Normal as it is. once in the gearbox, you ll find one bearing only on the spur shaft. it will be installed on the left end of the shaft. the right side (where the shaft exits the gear box) just has a clip and rubber piece to keep dirt out. that is where the Perverbial Missing Spur Shaft Bearing goes. once you install the "missing bearing" the slop will be minimal if any at all. i was a bit surprised at the amount of play in the shaft in stock form. but once the gear box is installed and the spur plate (with bearing ) is installed the shaft is quite rigid and solid. but adding the Missing bearing is a good piece of mind thing to do imo. but the setup should be fine, once fully assembled without it.

the diff though looked to be Way to much slap. i would expect a siezed diff bearing or maybe the bushing is worn away inside the diff cup where the axle passes thru the case, or the diff gears (inside the diff) are shot and need to be replaced. i would lean to the last of these options and also suspect the diff housing is warped and some diff gears are toasted.
grab TRs diff saver cases and a set of gears ( HPI WILL warrenty them, typically with a new full DIFF!) and bearings and re do the diff. i have found no need for the HD Gears for the gear box, unless your looking to shave weight.

with TRs case installed on the diff, you can also start to over fill the diff ( more than just to the cross pins which is bout 1/2 full) to do a bit more tuning of the diff. currently im running stock 1000w oil, but next teardown im going back to 30,000 diff oil.
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they warrented mine at about 4 or 5 gallons in.
just called them up and explained to the guy the diff took a poop on me.
took and forwarded pics to CS of the chipped,chewed diff gears.
after 2 weeks, i didnt hear anything or recieve anything, so i called and talked to the guy again. he had just returned from a weeks vacation, which is why it didnt get sent out to me at first. 10 days later, a full diff showed up, i only expected a case and diff gears. so i called back to thank them, and that when i was told they typically will send out a full diff>

I was very pleased about it. instead of "Buying" a new diff, i was able to buy TRs diff saver cases and put that with my diff. all good now.
I called and told them that the diff broke at the bearing and that locked the bearing causing damage to the casing. They told me that it typically will go bad the fist few weeks when going off big jumps and that it would not be covered. I am going to send them the photos of it and see if that still is their decision. Dang it!:no:
Does the Turtle case replace the whole inside case or go around the stock case? I need to know what I need to save and buy. Luckily I only need the cases and the bearings + the missing bearing.:ph34r:
TRs case saves comes with a set of stock cases. the stock case needs to be mildly modified for the TR diff saver case to fit.

just take the internal gears out of the new diff, and slide them into the TR cases, drop a new Diff oring in, and fill to 1/2 way and put together.

what i did, is take 1/2 the case off the stocker, then slide the same 1/2 case from the TR set on, then flipped over and repeat for the other side.
once you pull the diff/gears out of the stock its a B I T C H to get them back in. its much easier to leave the internals in one half the case and fit the other half on.

i guess id be telling the guy you wernt JUMPIN big and hard, and this happened while running in normally flat surfaces.

Then i would point out there MUST be some issue with the stock plastic diff case or else they would of designed and be releasing a Cast ALUMINUM diff case in the SS kit. seems like that alone would say, NEEDS to be Warrenteed.

the thing has a 2 yr warrenty on it on defective parts. 70% plus diff failures in normal operating conditions sure sounds like DEFECTIVE Parts to me.
OOps!:blush: guess I'm going to learn how to put it together from scratch. I will send in the photos of the diff and see what they do. Saving up for the upgrade, guess the tires will have to wait untill they fall off.:clown: So really if I have the gears and order up the bearings from TFE I should be good to go with the Diff except for buying the new cover. Good thing I saw it before it got worse and chewed up the gearing.

Than you,


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wow, that is pretty rusted.
hows the Diff gears? doest eh diff spin properly without binding up?
if so then it could be a fairly simple fix with a new gear box and bearings.
if the diff is functioning properly, then thats a bonus. put a set of TR Cased with the internal diff gears and you ll have a solid diff.

sucky part is the diff needs to come apart to get that drive cup off so you can replace that bearing.
Ya, the diff works properly and the gears are all in good shape. The only bearings effected was the one on the broken side. Seems odd there is no seal to the casing to keep moisture out? All I will need is new bearings and the TR case and I should be good to go. I filled the diff with oil when I got it and it seemed like it had 1/4 of the oil I put in it still left? Oh well, sent the photos to HPI see if they do anything but till then saving up for the TR case and TFE bearing kit. Thanks for your help.
i would imagine if only the Bearing is bad, then its unlikely you ll get a diff. but maybe a set of bearings.

as long as the case isnt warped, adding the TR Diff Saver Case and the TFE bearings should rock solid up the diff.
That ring on the outside of the diff cup is a piece of the case that is no longer there now that I took the cup shaft out.:crying: New case needed, it comes with the TR case saver though right? Thats what I'm thinking (hoping) I will go with.
yes TR Diff Saver case does indeed come with a set of Diff cases. they need to be lightly modified to work wiht the Alloy cases. so a stock unmodified case wont work. atleast not with out a bit of finesse with a dremel
Well good news, they(HPI) will be replacing the two cases and the two bearings under warranty. At 1st they denied it, but I wrote back and said what you said (Timmahh) and told them all that is damaged after tearing it down are those items, which isn't much but shouldn't of happened.:) (All smiles) Now have to save quick and get the TTR case and put it back together.
On another note kinda funny on the sloppy bearing thing up front. I tore it apart and found a stuck(froze) bearing, tore the bearing apart cleaned and re-greased and the slop magically went away. What the heck? Oh, well smiles again.:)

Before cleaning bearings:

After cleaning bearings:

There isn't a right or wrong way of installing a bearing is there? Aren't they the same on both sides?
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